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c618de01 SC |
1 | /* BFD support for handling relocation entries. |
2 | Copyright (C) 1990-1991 Free Software Foundation, Inc. | |
3 | Written by Cygnus Support. | |
4 | ||
5 | This file is part of BFD, the Binary File Descriptor library. | |
6 | ||
7 | This program is free software; you can redistribute it and/or modify | |
8 | it under the terms of the GNU General Public License as published by | |
9 | the Free Software Foundation; either version 2 of the License, or | |
10 | (at your option) any later version. | |
11 | ||
12 | This program is distributed in the hope that it will be useful, | |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | GNU General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
18 | along with this program; if not, write to the Free Software | |
19 | Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ | |
20 | ||
0cda46cf SC |
21 | /* |
22 | SECTION | |
23 | Relocations | |
985fca12 | 24 | |
0cda46cf SC |
25 | BFD maintains relocations in much the same was as it maintains |
26 | symbols; they are left alone until required, then read in | |
27 | en-mass and traslated into an internal form. There is a common | |
28 | routine <<bfd_perform_relocation>> which acts upon the | |
29 | canonical form to to the actual fixup. | |
985fca12 | 30 | |
0cda46cf SC |
31 | Note that relocations are maintained on a per section basis, |
32 | whilst symbols are maintained on a per BFD basis. | |
985fca12 | 33 | |
0cda46cf SC |
34 | All a back end has to do to fit the BFD interface is to create |
35 | as many <<struct reloc_cache_entry>> as there are relocations | |
36 | in a particuar section, and fill in the right bits: | |
985fca12 SC |
37 | |
38 | @menu | |
e98e6ec1 SC |
39 | @* typedef arelent:: |
40 | @* howto manager:: | |
985fca12 SC |
41 | @end menu |
42 | ||
43 | */ | |
985fca12 | 44 | #include "bfd.h" |
0cda46cf | 45 | #include "sysdep.h" |
985fca12 | 46 | #include "libbfd.h" |
e98e6ec1 | 47 | #include "seclet.h" |
c26d7d17 SC |
48 | /* |
49 | DOCDD | |
e98e6ec1 SC |
50 | INODE |
51 | typedef arelent, howto manager, Relocations, Relocations | |
985fca12 | 52 | |
0cda46cf SC |
53 | SUBSECTION |
54 | typedef arelent | |
985fca12 | 55 | |
e98e6ec1 | 56 | This is the structure of a relocation entry: |
985fca12 | 57 | |
e98e6ec1 SC |
58 | CODE_FRAGMENT |
59 | . | |
60 | .typedef enum bfd_reloc_status | |
61 | .{ | |
62 | . {* No errors detected *} | |
0cda46cf | 63 | . bfd_reloc_ok, |
e98e6ec1 SC |
64 | . |
65 | . {* The relocation was performed, but there was an overflow. *} | |
0cda46cf | 66 | . bfd_reloc_overflow, |
e98e6ec1 SC |
67 | . |
68 | . {* The address to relocate was not within the section supplied*} | |
0cda46cf | 69 | . bfd_reloc_outofrange, |
e98e6ec1 SC |
70 | . |
71 | . {* Used by special functions *} | |
0cda46cf | 72 | . bfd_reloc_continue, |
e98e6ec1 SC |
73 | . |
74 | . {* Unused *} | |
0cda46cf | 75 | . bfd_reloc_notsupported, |
e98e6ec1 SC |
76 | . |
77 | . {* Unsupported relocation size requested. *} | |
0cda46cf | 78 | . bfd_reloc_other, |
e98e6ec1 SC |
79 | . |
80 | . {* The symbol to relocate against was undefined.*} | |
0cda46cf | 81 | . bfd_reloc_undefined, |
e98e6ec1 SC |
82 | . |
83 | . {* The relocation was performed, but may not be ok - presently | |
84 | . generated only when linking i960 coff files with i960 b.out | |
85 | . symbols. *} | |
0cda46cf | 86 | . bfd_reloc_dangerous |
e98e6ec1 | 87 | . } |
0cda46cf | 88 | . bfd_reloc_status_type; |
e98e6ec1 SC |
89 | . |
90 | . | |
0cda46cf SC |
91 | .typedef struct reloc_cache_entry |
92 | .{ | |
e98e6ec1 SC |
93 | . {* A pointer into the canonical table of pointers *} |
94 | . struct symbol_cache_entry **sym_ptr_ptr; | |
95 | . | |
96 | . {* offset in section *} | |
97 | . rawdata_offset address; | |
98 | . | |
99 | . {* addend for relocation value *} | |
100 | . bfd_vma addend; | |
101 | . | |
102 | . {* Pointer to how to perform the required relocation *} | |
103 | . CONST struct reloc_howto_struct *howto; | |
104 | . | |
105 | .} arelent; | |
985fca12 | 106 | |
e98e6ec1 | 107 | */ |
985fca12 | 108 | |
e98e6ec1 SC |
109 | /* |
110 | DESCRIPTION | |
985fca12 | 111 | |
e98e6ec1 | 112 | Here is a description of each of the fields within a relent: |
985fca12 | 113 | |
e98e6ec1 | 114 | o sym_ptr_ptr |
985fca12 | 115 | |
e98e6ec1 SC |
116 | The symbol table pointer points to a pointer to the symbol |
117 | associated with the relocation request. This would naturally | |
118 | be the pointer into the table returned by the back end's | |
119 | get_symtab action. @xref{Symbols}. The symbol is referenced | |
120 | through a pointer to a pointer so that tools like the linker | |
121 | can fix up all the symbols of the same name by modifying only | |
122 | one pointer. The relocation routine looks in the symbol and | |
123 | uses the base of the section the symbol is attached to and the | |
124 | value of the symbol as the initial relocation offset. If the | |
125 | symbol pointer is zero, then the section provided is looked up. | |
985fca12 | 126 | |
e98e6ec1 | 127 | o address |
985fca12 | 128 | |
e98e6ec1 SC |
129 | The address field gives the offset in bytes from the base of |
130 | the section data which owns the relocation record to the first | |
131 | byte of relocatable information. The actual data relocated | |
132 | will be relative to this point - for example, a relocation | |
133 | type which modifies the bottom two bytes of a four byte word | |
134 | would not touch the first byte pointed to in a big endian | |
c26d7d17 SC |
135 | world. |
136 | ||
137 | o addend | |
138 | ||
139 | The addend is a value provided by the back end to be added (!) | |
140 | to the relocation offset. Its interpretation is dependent upon | |
141 | the howto. For example, on the 68k the code: | |
985fca12 | 142 | |
985fca12 | 143 | |
e98e6ec1 SC |
144 | | char foo[]; |
145 | | main() | |
146 | | { | |
147 | | return foo[0x12345678]; | |
148 | | } | |
985fca12 | 149 | |
e98e6ec1 | 150 | Could be compiled into: |
985fca12 | 151 | |
e98e6ec1 SC |
152 | | linkw fp,#-4 |
153 | | moveb @@#12345678,d0 | |
154 | | extbl d0 | |
155 | | unlk fp | |
156 | | rts | |
985fca12 | 157 | |
985fca12 | 158 | |
e98e6ec1 SC |
159 | This could create a reloc pointing to foo, but leave the |
160 | offset in the data (something like) | |
0cda46cf | 161 | |
985fca12 | 162 | |
e98e6ec1 SC |
163 | |RELOCATION RECORDS FOR [.text]: |
164 | |offset type value | |
165 | |00000006 32 _foo | |
166 | | | |
167 | |00000000 4e56 fffc ; linkw fp,#-4 | |
168 | |00000004 1039 1234 5678 ; moveb @@#12345678,d0 | |
169 | |0000000a 49c0 ; extbl d0 | |
170 | |0000000c 4e5e ; unlk fp | |
171 | |0000000e 4e75 ; rts | |
0cda46cf | 172 | |
985fca12 | 173 | |
e98e6ec1 SC |
174 | Using coff and an 88k, some instructions don't have enough |
175 | space in them to represent the full address range, and | |
176 | pointers have to be loaded in two parts. So you'd get something like: | |
0cda46cf | 177 | |
985fca12 | 178 | |
e98e6ec1 SC |
179 | | or.u r13,r0,hi16(_foo+0x12345678) |
180 | | ld.b r2,r13,lo16(_foo+0x12345678) | |
181 | | jmp r1 | |
985fca12 | 182 | |
985fca12 | 183 | |
e98e6ec1 SC |
184 | This whould create two relocs, both pointing to _foo, and with |
185 | 0x12340000 in their addend field. The data would consist of: | |
0cda46cf | 186 | |
985fca12 | 187 | |
e98e6ec1 SC |
188 | |RELOCATION RECORDS FOR [.text]: |
189 | |offset type value | |
190 | |00000002 HVRT16 _foo+0x12340000 | |
191 | |00000006 LVRT16 _foo+0x12340000 | |
985fca12 | 192 | |
e98e6ec1 SC |
193 | |00000000 5da05678 ; or.u r13,r0,0x5678 |
194 | |00000004 1c4d5678 ; ld.b r2,r13,0x5678 | |
195 | |00000008 f400c001 ; jmp r1 | |
985fca12 | 196 | |
0cda46cf | 197 | |
e98e6ec1 SC |
198 | The relocation routine digs out the value from the data, adds |
199 | it to the addend to get the original offset and then adds the | |
200 | value of _foo. Note that all 32 bits have to be kept around | |
201 | somewhere, to cope with carry from bit 15 to bit 16. | |
985fca12 | 202 | |
e98e6ec1 SC |
203 | On further example is the sparc and the a.out format. The |
204 | sparc has a similar problem to the 88k, in that some | |
205 | instructions don't have room for an entire offset, but on the | |
206 | sparc the parts are created odd sized lumps. The designers of | |
207 | the a.out format chose not to use the data within the section | |
208 | for storing part of the offset; all the offset is kept within | |
209 | the reloc. Any thing in the data should be ignored. | |
0cda46cf | 210 | |
e98e6ec1 SC |
211 | | save %sp,-112,%sp |
212 | | sethi %hi(_foo+0x12345678),%g2 | |
213 | | ldsb [%g2+%lo(_foo+0x12345678)],%i0 | |
214 | | ret | |
215 | | restore | |
0cda46cf | 216 | |
e98e6ec1 SC |
217 | Both relocs contains a pointer to foo, and the offsets would |
218 | contain junk. | |
985fca12 | 219 | |
0cda46cf | 220 | |
e98e6ec1 SC |
221 | |RELOCATION RECORDS FOR [.text]: |
222 | |offset type value | |
223 | |00000004 HI22 _foo+0x12345678 | |
224 | |00000008 LO10 _foo+0x12345678 | |
225 | ||
226 | |00000000 9de3bf90 ; save %sp,-112,%sp | |
227 | |00000004 05000000 ; sethi %hi(_foo+0),%g2 | |
228 | |00000008 f048a000 ; ldsb [%g2+%lo(_foo+0)],%i0 | |
229 | |0000000c 81c7e008 ; ret | |
230 | |00000010 81e80000 ; restore | |
231 | ||
0cda46cf | 232 | |
e98e6ec1 SC |
233 | o howto |
234 | ||
235 | The howto field can be imagined as a | |
236 | relocation instruction. It is a pointer to a struct which | |
237 | contains information on what to do with all the other | |
238 | information in the reloc record and data section. A back end | |
239 | would normally have a relocation instruction set and turn | |
240 | relocations into pointers to the correct structure on input - | |
241 | but it would be possible to create each howto field on demand. | |
242 | ||
985fca12 SC |
243 | */ |
244 | ||
245 | ||
0cda46cf SC |
246 | /* |
247 | SUBSUBSECTION | |
e98e6ec1 | 248 | <<reloc_howto_type>> |
985fca12 | 249 | |
e98e6ec1 SC |
250 | The <<reloc_howto_type>> is a structure which contains all the |
251 | information that BFD needs to know to tie up a back end's data. | |
985fca12 | 252 | |
e98e6ec1 | 253 | CODE_FRAGMENT |
5022aea5 | 254 | .struct symbol_cache_entry; {* Forward declaration *} |
e98e6ec1 | 255 | . |
0cda46cf SC |
256 | .typedef CONST struct reloc_howto_struct |
257 | .{ | |
e98e6ec1 SC |
258 | . {* The type field has mainly a documetary use - the back end can |
259 | . to what it wants with it, though the normally the back end's | |
260 | . external idea of what a reloc number would be would be stored | |
261 | . in this field. For example, the a PC relative word relocation | |
262 | . in a coff environment would have the type 023 - because that's | |
263 | . what the outside world calls a R_PCRWORD reloc. *} | |
0cda46cf | 264 | . unsigned int type; |
e98e6ec1 SC |
265 | . |
266 | . {* The value the final relocation is shifted right by. This drops | |
267 | . unwanted data from the relocation. *} | |
0cda46cf | 268 | . unsigned int rightshift; |
e98e6ec1 SC |
269 | . |
270 | . {* The size of the item to be relocated - 0, is one byte, 1 is 2 | |
c26d7d17 SC |
271 | . bytes, 3 is four bytes. A -ve value indicates that the |
272 | . result is to be subtracted from the data*} | |
273 | . int size; | |
e98e6ec1 SC |
274 | . |
275 | . {* Now obsolete *} | |
0cda46cf | 276 | . unsigned int bitsize; |
e98e6ec1 SC |
277 | . |
278 | . {* Notes that the relocation is relative to the location in the | |
279 | . data section of the addend. The relocation function will | |
280 | . subtract from the relocation value the address of the location | |
281 | . being relocated. *} | |
0cda46cf | 282 | . boolean pc_relative; |
e98e6ec1 SC |
283 | . |
284 | . {* Now obsolete *} | |
0cda46cf | 285 | . unsigned int bitpos; |
e98e6ec1 SC |
286 | . |
287 | . {* Now obsolete *} | |
0cda46cf | 288 | . boolean absolute; |
e98e6ec1 SC |
289 | . |
290 | . {* Causes the relocation routine to return an error if overflow | |
291 | . is detected when relocating. *} | |
0cda46cf | 292 | . boolean complain_on_overflow; |
e98e6ec1 SC |
293 | . |
294 | . {* If this field is non null, then the supplied function is | |
295 | . called rather than the normal function. This allows really | |
296 | . strange relocation methods to be accomodated (eg, i960 callj | |
297 | . instructions). *} | |
fefb4b30 JG |
298 | . bfd_reloc_status_type (*special_function) |
299 | . PARAMS ((bfd *abfd, | |
5022aea5 SC |
300 | . arelent *reloc_entry, |
301 | . struct symbol_cache_entry *symbol, | |
302 | . PTR data, | |
8070f29d | 303 | . asection *input_section, |
fefb4b30 | 304 | . bfd *output_bfd)); |
e98e6ec1 SC |
305 | . |
306 | . {* The textual name of the relocation type. *} | |
0cda46cf | 307 | . char *name; |
e98e6ec1 SC |
308 | . |
309 | . {* When performing a partial link, some formats must modify the | |
310 | . relocations rather than the data - this flag signals this.*} | |
0cda46cf | 311 | . boolean partial_inplace; |
e98e6ec1 SC |
312 | . |
313 | . {* The src_mask is used to select what parts of the read in data | |
314 | . are to be used in the relocation sum. Eg, if this was an 8 bit | |
315 | . bit of data which we read and relocated, this would be | |
316 | . 0x000000ff. When we have relocs which have an addend, such as | |
317 | . sun4 extended relocs, the value in the offset part of a | |
318 | . relocating field is garbage so we never use it. In this case | |
319 | . the mask would be 0x00000000. *} | |
0cda46cf | 320 | . bfd_word src_mask; |
e98e6ec1 SC |
321 | . |
322 | . {* The dst_mask is what parts of the instruction are replaced | |
323 | . into the instruction. In most cases src_mask == dst_mask, | |
324 | . except in the above special case, where dst_mask would be | |
325 | . 0x000000ff, and src_mask would be 0x00000000. *} | |
0cda46cf | 326 | . bfd_word dst_mask; |
e98e6ec1 SC |
327 | . |
328 | . {* When some formats create PC relative instructions, they leave | |
329 | . the value of the pc of the place being relocated in the offset | |
330 | . slot of the instruction, so that a PC relative relocation can | |
331 | . be made just by adding in an ordinary offset (eg sun3 a.out). | |
332 | . Some formats leave the displacement part of an instruction | |
333 | . empty (eg m88k bcs), this flag signals the fact.*} | |
0cda46cf | 334 | . boolean pcrel_offset; |
e98e6ec1 | 335 | . |
0cda46cf | 336 | .} reloc_howto_type; |
985fca12 | 337 | |
0cda46cf | 338 | */ |
985fca12 | 339 | |
0cda46cf SC |
340 | /* |
341 | FUNCTION | |
e98e6ec1 SC |
342 | the HOWTO macro |
343 | ||
0cda46cf SC |
344 | DESCRIPTION |
345 | The HOWTO define is horrible and will go away. | |
346 | ||
347 | ||
348 | .#define HOWTO(C, R,S,B, P, BI, ABS, O, SF, NAME, INPLACE, MASKSRC, MASKDST, PC) \ | |
349 | . {(unsigned)C,R,S,B, P, BI, ABS,O,SF,NAME,INPLACE,MASKSRC,MASKDST,PC} | |
350 | ||
351 | DESCRIPTION | |
352 | And will be replaced with the totally magic way. But for the | |
353 | moment, we are compatible, so do it this way.. | |
354 | ||
355 | ||
356 | .#define NEWHOWTO( FUNCTION, NAME,SIZE,REL,IN) HOWTO(0,0,SIZE,0,REL,0,false,false,FUNCTION, NAME,false,0,0,IN) | |
357 | . | |
358 | DESCRIPTION | |
359 | Helper routine to turn a symbol into a relocation value. | |
360 | ||
e98e6ec1 SC |
361 | .#define HOWTO_PREPARE(relocation, symbol) \ |
362 | . { \ | |
363 | . if (symbol != (asymbol *)NULL) { \ | |
364 | . if (symbol->section == &bfd_com_section) { \ | |
365 | . relocation = 0; \ | |
366 | . } \ | |
367 | . else { \ | |
368 | . relocation = symbol->value; \ | |
369 | . } \ | |
370 | . } \ | |
371 | .} | |
985fca12 SC |
372 | |
373 | */ | |
374 | ||
0cda46cf SC |
375 | /* |
376 | TYPEDEF | |
377 | reloc_chain | |
985fca12 | 378 | |
0cda46cf | 379 | DESCRIPTION |
985fca12 | 380 | |
0cda46cf | 381 | How relocs are tied together |
985fca12 | 382 | |
0cda46cf SC |
383 | .typedef unsigned char bfd_byte; |
384 | . | |
385 | .typedef struct relent_chain { | |
386 | . arelent relent; | |
387 | . struct relent_chain *next; | |
388 | .} arelent_chain; | |
985fca12 SC |
389 | |
390 | */ | |
391 | ||
392 | ||
393 | ||
0cda46cf SC |
394 | /* |
395 | FUNCTION | |
396 | bfd_perform_relocation | |
397 | ||
e98e6ec1 SC |
398 | SYNOPSIS |
399 | bfd_reloc_status_type | |
400 | bfd_perform_relocation | |
401 | (bfd * abfd, | |
402 | arelent *reloc_entry, | |
403 | PTR data, | |
404 | asection *input_section, | |
405 | bfd *output_bfd); | |
406 | ||
0cda46cf SC |
407 | DESCRIPTION |
408 | If an output_bfd is supplied to this function the generated | |
409 | image will be relocatable, the relocations are copied to the | |
410 | output file after they have been changed to reflect the new | |
411 | state of the world. There are two ways of reflecting the | |
412 | results of partial linkage in an output file; by modifying the | |
413 | output data in place, and by modifying the relocation record. | |
414 | Some native formats (eg basic a.out and basic coff) have no | |
415 | way of specifying an addend in the relocation type, so the | |
416 | addend has to go in the output data. This is no big deal | |
417 | since in these formats the output data slot will always be big | |
418 | enough for the addend. Complex reloc types with addends were | |
419 | invented to solve just this problem. | |
420 | ||
985fca12 SC |
421 | */ |
422 | ||
423 | ||
0cda46cf | 424 | bfd_reloc_status_type |
985fca12 SC |
425 | DEFUN(bfd_perform_relocation,(abfd, |
426 | reloc_entry, | |
427 | data, | |
428 | input_section, | |
429 | output_bfd), | |
430 | bfd *abfd AND | |
431 | arelent *reloc_entry AND | |
432 | PTR data AND | |
433 | asection *input_section AND | |
434 | bfd *output_bfd) | |
435 | { | |
436 | bfd_vma relocation; | |
0cda46cf | 437 | bfd_reloc_status_type flag = bfd_reloc_ok; |
985fca12 SC |
438 | bfd_vma addr = reloc_entry->address ; |
439 | bfd_vma output_base = 0; | |
440 | reloc_howto_type *howto = reloc_entry->howto; | |
e98e6ec1 SC |
441 | asection *reloc_target_output_section ; |
442 | ||
985fca12 SC |
443 | asymbol *symbol; |
444 | ||
e98e6ec1 | 445 | symbol = *( reloc_entry->sym_ptr_ptr); |
5022aea5 SC |
446 | if ((symbol->section == &bfd_abs_section) |
447 | && output_bfd != (bfd *)NULL) | |
448 | { | |
449 | reloc_entry->address += input_section->output_offset; | |
450 | ||
451 | return bfd_reloc_ok; | |
452 | ||
453 | } | |
454 | ||
e98e6ec1 | 455 | if ((symbol->section == &bfd_und_section) && output_bfd == (bfd *)NULL) { |
5022aea5 SC |
456 | flag = bfd_reloc_undefined; |
457 | } | |
985fca12 | 458 | |
8070f29d | 459 | if (howto->special_function) { |
5022aea5 SC |
460 | bfd_reloc_status_type cont; |
461 | cont = howto->special_function(abfd, | |
462 | reloc_entry, | |
463 | symbol, | |
464 | data, | |
8070f29d KR |
465 | input_section, |
466 | output_bfd); | |
5022aea5 SC |
467 | if (cont != bfd_reloc_continue) return cont; |
468 | } | |
985fca12 SC |
469 | |
470 | /* | |
471 | Work out which section the relocation is targetted at and the | |
472 | initial relocation command value. | |
473 | */ | |
474 | ||
475 | ||
e98e6ec1 | 476 | if (symbol->section == &bfd_com_section) { |
5022aea5 SC |
477 | relocation = 0; |
478 | } | |
e98e6ec1 | 479 | else { |
5022aea5 SC |
480 | relocation = symbol->value; |
481 | } | |
985fca12 | 482 | |
985fca12 | 483 | |
e98e6ec1 | 484 | reloc_target_output_section = symbol->section->output_section; |
985fca12 | 485 | |
e98e6ec1 | 486 | if (output_bfd && howto->partial_inplace==false) { |
5022aea5 SC |
487 | output_base = 0; |
488 | } | |
e98e6ec1 | 489 | else { |
5022aea5 | 490 | output_base = reloc_target_output_section->vma; |
985fca12 | 491 | |
5022aea5 | 492 | } |
985fca12 | 493 | |
e98e6ec1 SC |
494 | relocation += output_base + symbol->section->output_offset; |
495 | ||
985fca12 SC |
496 | |
497 | relocation += reloc_entry->addend ; | |
498 | ||
499 | ||
e98e6ec1 SC |
500 | if(reloc_entry->address > input_section->_cooked_size) |
501 | { | |
502 | return bfd_reloc_outofrange; | |
503 | } | |
985fca12 SC |
504 | |
505 | ||
506 | if (howto->pc_relative == true) | |
e98e6ec1 SC |
507 | { |
508 | /* | |
509 | Anything which started out as pc relative should end up that | |
510 | way too. | |
511 | ||
512 | There are two ways we can see a pcrel instruction. Sometimes | |
513 | the pcrel displacement has been partially calculated, it | |
514 | includes the distance from the start of the section to the | |
515 | instruction in it (eg sun3), and sometimes the field is | |
516 | totally blank - eg m88kbcs. | |
517 | */ | |
985fca12 SC |
518 | |
519 | ||
e98e6ec1 SC |
520 | relocation -= |
521 | input_section->output_section->vma + input_section->output_offset; | |
985fca12 | 522 | |
e98e6ec1 | 523 | if (howto->pcrel_offset == true) { |
5022aea5 SC |
524 | relocation -= reloc_entry->address; |
525 | } | |
985fca12 | 526 | |
e98e6ec1 SC |
527 | } |
528 | ||
c26d7d17 SC |
529 | if (output_bfd!= (bfd *)NULL) |
530 | { | |
531 | if ( howto->partial_inplace == false) | |
532 | { | |
5022aea5 SC |
533 | /* |
534 | This is a partial relocation, and we want to apply the relocation | |
535 | to the reloc entry rather than the raw data. Modify the reloc | |
536 | inplace to reflect what we now know. | |
537 | */ | |
538 | reloc_entry->addend = relocation ; | |
539 | reloc_entry->address += input_section->output_offset; | |
540 | return flag; | |
541 | } | |
542 | else | |
543 | { | |
544 | /* This is a partial relocation, but inplace, so modify the | |
545 | reloc record a bit. | |
546 | ||
547 | If we've relocated with a symbol with a section, change | |
548 | into a ref to the section belonging to the symbol | |
549 | */ | |
e98e6ec1 | 550 | |
c26d7d17 SC |
551 | reloc_entry->address += input_section->output_offset; |
552 | ||
553 | if (abfd->xvec->flavour == bfd_target_coff_flavour) | |
554 | { | |
555 | relocation -= reloc_entry->addend; | |
556 | reloc_entry->addend = 0; | |
557 | } | |
558 | else | |
559 | { | |
560 | reloc_entry->addend = relocation ; | |
561 | } | |
985fca12 | 562 | } |
5022aea5 | 563 | } |
e98e6ec1 SC |
564 | else |
565 | { | |
5022aea5 SC |
566 | reloc_entry->addend = 0; |
567 | } | |
e98e6ec1 | 568 | |
985fca12 | 569 | |
985fca12 SC |
570 | /* |
571 | Either we are relocating all the way, or we don't want to apply | |
572 | the relocation to the reloc entry (probably because there isn't | |
573 | any room in the output format to describe addends to relocs) | |
574 | */ | |
575 | relocation >>= howto->rightshift; | |
576 | ||
577 | /* Shift everything up to where it's going to be used */ | |
578 | ||
579 | relocation <<= howto->bitpos; | |
580 | ||
581 | /* Wait for the day when all have the mask in them */ | |
582 | ||
583 | /* What we do: | |
584 | i instruction to be left alone | |
585 | o offset within instruction | |
586 | r relocation offset to apply | |
587 | S src mask | |
588 | D dst mask | |
589 | N ~dst mask | |
590 | A part 1 | |
591 | B part 2 | |
592 | R result | |
593 | ||
594 | Do this: | |
595 | i i i i i o o o o o from bfd_get<size> | |
596 | and S S S S S to get the size offset we want | |
597 | + r r r r r r r r r r to get the final value to place | |
598 | and D D D D D to chop to right size | |
599 | ----------------------- | |
600 | A A A A A | |
601 | And this: | |
602 | ... i i i i i o o o o o from bfd_get<size> | |
603 | and N N N N N get instruction | |
604 | ----------------------- | |
605 | ... B B B B B | |
606 | ||
607 | And then: | |
608 | B B B B B | |
609 | or A A A A A | |
610 | ----------------------- | |
611 | R R R R R R R R R R put into bfd_put<size> | |
612 | */ | |
613 | ||
614 | #define DOIT(x) \ | |
615 | x = ( (x & ~howto->dst_mask) | (((x & howto->src_mask) + relocation) & howto->dst_mask)) | |
616 | ||
e98e6ec1 SC |
617 | switch (howto->size) |
618 | { | |
5022aea5 SC |
619 | case 0: |
620 | { | |
621 | char x = bfd_get_8(abfd, (char *)data + addr); | |
622 | DOIT(x); | |
623 | bfd_put_8(abfd,x, (unsigned char *) data + addr); | |
624 | } | |
e98e6ec1 SC |
625 | break; |
626 | ||
5022aea5 SC |
627 | case 1: |
628 | { | |
629 | short x = bfd_get_16(abfd, (bfd_byte *)data + addr); | |
630 | DOIT(x); | |
631 | bfd_put_16(abfd, x, (unsigned char *)data + addr); | |
632 | } | |
e98e6ec1 | 633 | break; |
5022aea5 SC |
634 | case 2: |
635 | { | |
636 | long x = bfd_get_32(abfd, (bfd_byte *) data + addr); | |
637 | DOIT(x); | |
638 | bfd_put_32(abfd,x, (bfd_byte *)data + addr); | |
639 | } | |
e98e6ec1 | 640 | break; |
c26d7d17 SC |
641 | case -2: |
642 | { | |
643 | long x = bfd_get_32(abfd, (bfd_byte *) data + addr); | |
644 | relocation = -relocation; | |
645 | DOIT(x); | |
646 | bfd_put_32(abfd,x, (bfd_byte *)data + addr); | |
647 | } | |
648 | break; | |
649 | ||
5022aea5 | 650 | case 3: |
e98e6ec1 SC |
651 | |
652 | /* Do nothing */ | |
653 | break; | |
5022aea5 | 654 | default: |
e98e6ec1 SC |
655 | return bfd_reloc_other; |
656 | } | |
985fca12 SC |
657 | |
658 | return flag; | |
659 | } | |
c618de01 SC |
660 | |
661 | ||
2cf44d7b | 662 | |
0cda46cf | 663 | /* |
c26d7d17 | 664 | DOCDD |
e98e6ec1 SC |
665 | INODE |
666 | howto manager, , typedef arelent, Relocations | |
667 | ||
0cda46cf SC |
668 | SECTION |
669 | The howto manager | |
2cf44d7b | 670 | |
0cda46cf SC |
671 | When an application wants to create a relocation, but doesn't |
672 | know what the target machine might call it, it can find out by | |
673 | using this bit of code. | |
2cf44d7b | 674 | |
0cda46cf | 675 | */ |
2cf44d7b | 676 | |
0cda46cf SC |
677 | /* |
678 | TYPEDEF | |
679 | bfd_reloc_code_type | |
2cf44d7b | 680 | |
0cda46cf SC |
681 | DESCRIPTION |
682 | The insides of a reloc code | |
683 | ||
e98e6ec1 SC |
684 | CODE_FRAGMENT |
685 | . | |
686 | .typedef enum bfd_reloc_code_real | |
c26d7d17 | 687 | . |
e98e6ec1 SC |
688 | .{ |
689 | . {* 16 bits wide, simple reloc *} | |
690 | . BFD_RELOC_16, | |
691 | . | |
692 | . {* 8 bits wide, but used to form an address like 0xffnn *} | |
0cda46cf | 693 | . BFD_RELOC_8_FFnn, |
e98e6ec1 SC |
694 | . |
695 | . {* 8 bits wide, simple *} | |
0cda46cf | 696 | . BFD_RELOC_8, |
e98e6ec1 SC |
697 | . |
698 | . {* 8 bits wide, pc relative *} | |
0cda46cf | 699 | . BFD_RELOC_8_PCREL, |
e98e6ec1 SC |
700 | . |
701 | . {* The type of reloc used to build a contructor table - at the | |
702 | . moment probably a 32 bit wide abs address, but the cpu can | |
703 | . choose. *} | |
704 | . | |
8070f29d KR |
705 | . BFD_RELOC_CTOR, |
706 | . | |
707 | . {* 32 bits wide, simple reloc *} | |
708 | . BFD_RELOC_32, | |
709 | . {* 32 bits, PC-relative *} | |
710 | . BFD_RELOC_32_PCREL, | |
711 | . | |
712 | . {* High 22 bits of 32-bit value; simple reloc. *} | |
713 | . BFD_RELOC_HI22, | |
714 | . {* Low 10 bits. *} | |
715 | . BFD_RELOC_LO10, | |
716 | . | |
717 | . {* Reloc types used for i960/b.out. *} | |
718 | . BFD_RELOC_24_PCREL, | |
719 | . BFD_RELOC_I960_CALLJ, | |
720 | . | |
721 | . BFD_RELOC_16_PCREL, | |
722 | . {* 32-bit pc-relative, shifted right 2 bits (i.e., 30-bit | |
723 | . word displacement, e.g. for SPARC) *} | |
724 | . BFD_RELOC_32_PCREL_S2, | |
725 | . | |
726 | . {* now for the sparc/elf codes *} | |
727 | . BFD_RELOC_NONE, {* actually used *} | |
728 | . BFD_RELOC_SPARC_WDISP22, | |
729 | . BFD_RELOC_SPARC22, | |
730 | . BFD_RELOC_SPARC13, | |
731 | . BFD_RELOC_SPARC_BASE13, | |
732 | . BFD_RELOC_SPARC_GOT10, | |
733 | . BFD_RELOC_SPARC_GOT13, | |
734 | . BFD_RELOC_SPARC_GOT22, | |
735 | . BFD_RELOC_SPARC_PC10, | |
736 | . BFD_RELOC_SPARC_PC22, | |
737 | . BFD_RELOC_SPARC_WPLT30, | |
738 | . BFD_RELOC_SPARC_COPY, | |
739 | . BFD_RELOC_SPARC_GLOB_DAT, | |
740 | . BFD_RELOC_SPARC_JMP_SLOT, | |
741 | . BFD_RELOC_SPARC_RELATIVE, | |
742 | . BFD_RELOC_SPARC_UA32, | |
743 | . | |
744 | . {* this one is a.out specific? *} | |
745 | . BFD_RELOC_SPARC_BASE22, | |
746 | . | |
747 | . {* this must be the highest numeric value *} | |
748 | . BFD_RELOC_UNUSED | |
0cda46cf | 749 | . } bfd_reloc_code_real_type; |
2cf44d7b SC |
750 | */ |
751 | ||
752 | ||
753 | ||
0cda46cf SC |
754 | /* |
755 | SECTION | |
756 | bfd_reloc_type_lookup | |
2cf44d7b | 757 | |
e98e6ec1 SC |
758 | SYNOPSIS |
759 | CONST struct reloc_howto_struct * | |
3860075f | 760 | bfd_reloc_type_lookup (bfd *abfd, bfd_reloc_code_real_type code); |
e98e6ec1 | 761 | |
0cda46cf SC |
762 | DESCRIPTION |
763 | This routine returns a pointer to a howto struct which when | |
764 | invoked, will perform the supplied relocation on data from the | |
765 | architecture noted. | |
2cf44d7b | 766 | |
2cf44d7b SC |
767 | */ |
768 | ||
769 | ||
770 | CONST struct reloc_howto_struct * | |
3860075f | 771 | DEFUN(bfd_reloc_type_lookup,(abfd, code), |
8070f29d | 772 | bfd *abfd AND |
3860075f | 773 | bfd_reloc_code_real_type code) |
2cf44d7b | 774 | { |
8070f29d | 775 | return BFD_SEND (abfd, reloc_type_lookup, (abfd, code)); |
2cf44d7b SC |
776 | } |
777 | ||
0cda46cf SC |
778 | static reloc_howto_type bfd_howto_32 = |
779 | HOWTO(0, 00,2,32,false,0,false,true,0,"VRT32", false,0xffffffff,0xffffffff,true); | |
2cf44d7b SC |
780 | |
781 | ||
0cda46cf | 782 | /* |
e98e6ec1 | 783 | INTERNAL_FUNCTION |
0cda46cf SC |
784 | bfd_default_reloc_type_lookup |
785 | ||
0cda46cf SC |
786 | SYNOPSIS |
787 | CONST struct reloc_howto_struct *bfd_default_reloc_type_lookup | |
788 | (CONST struct bfd_arch_info *, | |
3860075f | 789 | bfd_reloc_code_real_type code); |
0cda46cf | 790 | |
e98e6ec1 SC |
791 | DESCRIPTION |
792 | Provides a default relocation lookuperer for any architectue | |
793 | ||
794 | ||
0cda46cf SC |
795 | */ |
796 | CONST struct reloc_howto_struct * | |
797 | DEFUN(bfd_default_reloc_type_lookup,(arch, code), | |
798 | CONST struct bfd_arch_info *arch AND | |
3860075f | 799 | bfd_reloc_code_real_type code) |
0cda46cf SC |
800 | { |
801 | switch (code) | |
802 | { | |
803 | case BFD_RELOC_CTOR: | |
804 | /* The type of reloc used in a ctor, which will be as wide as the | |
805 | address - so either a 64, 32, or 16 bitter.. */ | |
806 | switch (arch->bits_per_address) { | |
807 | case 64: | |
808 | BFD_FAIL(); | |
809 | case 32: | |
810 | return &bfd_howto_32; | |
811 | case 16: | |
812 | BFD_FAIL(); | |
813 | default: | |
814 | BFD_FAIL(); | |
815 | } | |
816 | default: | |
817 | BFD_FAIL(); | |
818 | } | |
c26d7d17 | 819 | return (CONST struct reloc_howto_struct *)NULL; |
0cda46cf | 820 | } |
e98e6ec1 SC |
821 | |
822 | ||
d58b7049 SC |
823 | /* |
824 | INTERNAL_FUNCTION | |
825 | bfd_generic_relax_section | |
826 | ||
827 | SYNOPSIS | |
828 | boolean bfd_generic_relax_section | |
829 | (bfd *abfd, | |
830 | asection *section, | |
5022aea5 | 831 | asymbol **symbols); |
d58b7049 SC |
832 | |
833 | DESCRIPTION | |
834 | Provides default handling for relaxing for back ends which | |
8070f29d | 835 | don't do relaxing -- i.e., does nothing. |
d58b7049 SC |
836 | */ |
837 | ||
838 | boolean | |
5022aea5 | 839 | DEFUN(bfd_generic_relax_section,(abfd, section, symbols), |
d58b7049 SC |
840 | bfd *abfd AND |
841 | asection *section AND | |
5022aea5 | 842 | asymbol **symbols) |
d58b7049 SC |
843 | { |
844 | ||
845 | return false; | |
846 | ||
847 | } | |
e98e6ec1 | 848 | |
d58b7049 | 849 | |
e98e6ec1 SC |
850 | /* |
851 | INTERNAL_FUNCTION | |
852 | bfd_generic_get_relocated_section_contents | |
853 | ||
854 | SYNOPSIS | |
855 | bfd_byte * | |
856 | bfd_generic_get_relocated_section_contents(bfd *abfd, | |
8070f29d KR |
857 | struct bfd_seclet_struct *seclet, |
858 | bfd_byte *data) | |
e98e6ec1 SC |
859 | |
860 | DESCRIPTION | |
861 | Provides default handling of relocation effort for back ends | |
862 | which can't be bothered to do it efficiently. | |
863 | ||
864 | */ | |
865 | ||
866 | bfd_byte * | |
8070f29d | 867 | DEFUN(bfd_generic_get_relocated_section_contents,(abfd, seclet, data), |
e98e6ec1 | 868 | bfd *abfd AND |
8070f29d KR |
869 | struct bfd_seclet_struct *seclet AND |
870 | bfd_byte *data) | |
e98e6ec1 SC |
871 | { |
872 | extern bfd_error_vector_type bfd_error_vector; | |
e98e6ec1 SC |
873 | |
874 | /* Get enough memory to hold the stuff */ | |
875 | bfd *input_bfd = seclet->u.indirect.section->owner; | |
876 | asection *input_section = seclet->u.indirect.section; | |
877 | ||
8070f29d | 878 | |
e98e6ec1 SC |
879 | |
880 | bfd_size_type reloc_size = bfd_get_reloc_upper_bound(input_bfd, | |
881 | input_section); | |
8070f29d | 882 | arelent **reloc_vector = (arelent **) alloca(reloc_size); |
e98e6ec1 SC |
883 | |
884 | /* read in the section */ | |
885 | bfd_get_section_contents(input_bfd, | |
886 | input_section, | |
887 | data, | |
888 | 0, | |
889 | input_section->_raw_size); | |
890 | ||
891 | /* We're not relaxing the section, so just copy the size info */ | |
892 | input_section->_cooked_size = input_section->_raw_size; | |
893 | input_section->reloc_done = true; | |
894 | ||
895 | ||
896 | if (bfd_canonicalize_reloc(input_bfd, | |
897 | input_section, | |
898 | reloc_vector, | |
899 | seclet->u.indirect.symbols) ) | |
900 | { | |
901 | arelent **parent; | |
902 | for (parent = reloc_vector; * parent != (arelent *)NULL; | |
903 | parent++) | |
904 | { | |
905 | bfd_reloc_status_type r= | |
906 | bfd_perform_relocation(input_bfd, | |
907 | *parent, | |
908 | data, | |
909 | input_section, 0); | |
910 | ||
911 | ||
912 | if (r != bfd_reloc_ok) | |
913 | { | |
e98e6ec1 SC |
914 | switch (r) |
915 | { | |
916 | case bfd_reloc_undefined: | |
917 | bfd_error_vector.undefined_symbol(*parent, seclet); | |
918 | break; | |
919 | case bfd_reloc_dangerous: | |
920 | bfd_error_vector.reloc_dangerous(*parent, seclet); | |
921 | break; | |
922 | case bfd_reloc_outofrange: | |
923 | case bfd_reloc_overflow: | |
924 | bfd_error_vector.reloc_value_truncated(*parent, seclet); | |
925 | break; | |
926 | default: | |
927 | abort(); | |
928 | break; | |
929 | } | |
930 | ||
931 | } | |
932 | } | |
933 | } | |
934 | ||
8070f29d | 935 | |
e98e6ec1 SC |
936 | return data; |
937 | ||
938 | ||
939 | } | |
940 |